linklater



March 3, 6 s. E. LINE-(LATER PUMP Filed Dec. 20, 1962 6. Z INVENTOR.

v Fra 1 56.61 Firal 5A MUEL. E. L/A/KLATE/e United States Patent PUMP Samuel E. Linklater, 309 Poppy Ava, Corona Del Mar, Calif. Filed Dec. 20, 1962, Ser. No. 246,278 8 Claims. (Cl. 103-434) This invention relates to liquid pumps and more particularly to an improved pump especially suitable for the pumping of molten metals and corrosive liquids.

The transferring of molten metals such as molten lead and of corrosive liquids, e.g. caustic and highly acid materials, is a troublesome and often difficult task. Main tenance of equipment is inherently costly and time consuming. Moving parts, including valves and pistons and the like, are subject to excessive corrosion and must be frequently replaced.

It is a principal object of the invention to provide a liquid pump employing no movable parts.

Another object of the invention is to provide a pump having a simplified structure.

A still further object of the invention is to provide a pump that may be employed for transporting of molten metals and corrosive materials and a pump requiring the minimum of maintenance.

The improved pump of the invention has a simple structure and in its preferred embodiment employs no valves, pistons or other movable parts in contact with the liquid. A pressurized fluid is employed for the propulsion of the liquid being pumped.

In the preferred embodiment of the liquid pump of the invention, there is provided a reservoir and a standpipe having an open upper end disposed Within the reservoir with the open upper end being located below the normal liquid level of the reservoir. A standpipe enclosure means, which may take the form of a tubular member open at its lower end, is placed about the standpipe with the opening being located below the upper end of the standpipe and above the reservoir bottom. The opening provides liquid communication between the interior of the standpipe enclosure means and the larger reservoir. Means are provided for introducing a pressurized fluid to the interior of the standpipe enclosure means above the normal liquid level. A liquid withdrawal means is connected to the standpipe for removing liquid therefrom in response to introduction of pressurized fluid to the interior of the standpipe enclosure means. The liquid withdrawal means may take the form of a pipe connected to the standpipe below its upper end and a valving means which permits flow of liquid therethrough with the introduction of pressurized air to the standpipe enclosure mews. In a preferred embodiment of the liquid pump, the liquid withdrawal means employs a liquid withdrawal pipe which is connected to the standpipe adjacent its lower end, the withdrawal pipe being provided with a segment above the normal liquid level of the reservoir which segment serves as a valving means.

The pump of the invention has proven especially suitable for the feeding of molten metal or other liquid at a predetermined amount per hour, this being achieved by providing means for the automatic and periodic interruption of the flow of pressurized fluid to the interior of the standpipe enclosure means. The pump can also be employed to dispense a predetermined amount of liquid, the cycle being repeated manually, as in the filling of a mold with molten metal. The pump is particularly suitable to use with molten lead but may be used advantageously with other liquids and molten metals. Air under pressure is normally employed as the propelling force although other pressurized gases may be used. Pressurized liquids of lower specific gravity than the liquid being pumped and insoluble therein may be employed in some applications.

3,123,15 Patented Mar. 3, 1%54 The reservoir of the liquid pump has a relatively large cross section. The standpipe has a cross section of significantly less area than the reservoir and the tubular standpipe enclosure member will normally have a cross section somewhat larger but of the same magnitude as the cross section of the standpipe. In a typical pump designed for the transfer of molten lead slowly and uniformly at a rate between 400 pounds and 1200 pounds per hour, the standpipe has a diameter of 4 inches. The standpipe enclosure means which is a tubular member has a diameter of 6 inches. The reservoir in which the standpipe and tubular means are disposed has a diameter of 28.5 inches. The liquid withdrawal pipe of this particular embodiment has a diameter of A of an inch.

The reservoir of the liquid pump desirably has a crosssectional area 3 to 200 times as great as the cross-sectional area of the standpipe and the standpipe enclosure means. The tubular standpipe enclosure means need be only slightly larger than the standpipe. Preferably, the internal area of the standpipe is relatively large compared to the cross section of the withdrawal pipe, generally being 20 to 40 times as great. With this proportioning of the withdrawal pipe and standpipe, variation in quantity of liquid pumped per cycle clue to fiuctations of the operating molten lead level is very small.

The foregoing objects and advantages of the invention, together with various other objects and advantages will become evident to those skilled in the art in light of the following disclosure and drawings. The drawings illustrate and the disclosure describes a preferred embodiment of the device of the present invention.

FIG. 1 is a top plan view of a preferred embodiment of the pump of the invention;

FIG. 2 is a longitudinal sectional view taken along line 22 of FIG. 1;

FIG. 3 is an enlarged fragmentary section taken from the site of line 3-3 of FIG. 2; and

FIGS. 47 are a series of schematic views partly in longitudinal section, illustrating the sequence involved in operation of the pump of the invention.

The particular pump illustrated in the drawings is designed to pump molten lead and includes a lead melting pot or kettle 10 which at its upper end is welded to a .circular' flange 12 which, in turn, rests on a cylindrical pot support frame 14. The pot 14) and pot support frame 14 are of conventional structure, with the frame holding the pot in an elevated position wherein its side and bottom are exposed to high temperature gases.

The pot or kettle 10 serves as the reservoir for the particular embodiment of the pump illustrated. The pump includes a standpipe 16 of tubular shape, closed at its lower end and open at its upper end. The closed end of the standpipe 16 is fixed to the inside bottom of the reservoir pot 10. The open upper end of the standpipe 16 is located below the normal liquid level of the reservoir pot 10. In the particular embodiment illustrated, the standpipe 16 is disposed within the pot closely adjacent its wall. The standpipe 16 has a cross-sectional area significantly less than the reservoir pot 10. In the particular embodiment illustrated, the area of the standpipe is about that of the reservoir pot Til.

A standpipe enclosure means 18, having the configuration of an inverted closed cylinder of tubular member 20, open at its lower end, is placed about the standpipe 16 with the inner wall of the tubular member being closely spaced thereto. The tubular member 20 and standpipe 16 have cross-sectional areas of the same general magnitude, with the cross-sectional area of the tubular member being somewhat larger than that of the standpipe. The open lower end ofthe tubular member 20 rests on two base ledges 22 and 24 and a Withdrawal pipe 26 which connects into the lower end of the standpipe 16. Liquid communication between the interior of the tubular member 29 and the larger area of the reservoir pot is provided by an annular space 21 between the standpipe 16 andtubular member 29 via the open end of the latter member. Thus, it is seen that the liquid level within the tubular member 20 is that of the reservoir pot 10. In the particular embodiment illustrated the pot 10, the standpipe 16 and tubular member 26 are all made of iron. An inlet pipe 28, also made of iron, extends through the open lower end of the tubular member 29 upwardly through the annular space 21 into the head space of the tubular member above the normal liquid level.

The tubular member 20 at its upper end is held in place by a retainer 3% which is made up of a U-shaped steel band 32 whose legs are fixed to the pot flange 12. A flat strap member 34 is slidably retained by the steel band 32. The inner end of the flat strap member 34 may be moved into and out of engagement with the closed top 35 of the tubular member 2i). The tubular member 29 is provided with a handle 36.

The withdrawal pipe 26 extends from the standpipe 16 under the lower edge of the tubular member 20 where it bends upwardly and parallels the side of the tubular member to an elevation above normal liquid level of the reservoir pot It The upper end of the withdrawal pipe as opens into a sloping outlet pipe 38. The outlet pipe 33 is divided into two segments and 42 which are joined together by a sleeve 44. The segment 42 extends through the side of the reservoir pot 10 and reaches beyond the side of the pot support frame 14. The outlet pipe segment 4% is open at both of its ends and is provided with a clean out hole 46 which aligns with the vertical portion of the withdrawal pipe 26. With the particular design illustrated, if there should occur a blockage in the outlet pipe segment 42, the molten lead or other liquid being pumped returns to the pot reservoir by the open end of the other segment 40.

The control system includes the aforementioned inlet pipe 23, a manual pressure regulator 48, a gauge 50, a needle valve 56, a solenoid valve 52 and a recycle timer 54. As the volume of air required is small, the system is not turned ofi during the short exhaust period.

The rate of feed per hour depends on the pressure of the air when the pump is operated on a constant repeat cycle, or if the pressure is constant, on the timing of the repeat cycle. The desired amount of feed may be obtained by adjusting the pressure regulator 48 to a suitable pressure.

FIG. 4 illustrates the pump at the beginning of a cycle and before air is introduced to the head space of the tubular member 20. At this point in time the solenoid valve 52 is open and pressurized air is being discharged directly to the atmosphere. The liquid level is at the same height in the reservoir pot 10 and the tubular member 20. The gauge 50 reads zero pressure. The recycle timer 54 then closes valve 52 and air is directed through the inlet pipe 28 to the head space of the tubular member 29, forcing the liquid therein downwardly. The displaced liquid leaves the tubular member 20 via the annular space 21 defined by the tubular member and the standpipe 16, escaping through the open bottom of the tubular member into the larger liquid reservoir of the pot 10. The transfer of liquid to the larger reservoir pot 10 from the smaller tubular member 20 causes only a slight rise in the height of the liquid level of the pot. The liquid level in the tubular member 20 is shown in FIG. 5 depressed to a level somewhat above the top of the standpipe 16. Continued introduction of pressurized air to the head space of the tubular member further depresses the liquid to the top of the standpipe as illustrated in FIG. 6. Further increase in pressure acts directly on the liquid in the standpipe 16, forcing liquid up the vertical leg of the withdrawal pipe 26 to the outlet pipe 38 as illustrated in FIG. 7.

With completion of the cycle, the cycle timer 54 opens the solenoid valve 52 causing the pressurized air to be discharged directly to atmosphere. The head space of the tubular enclosure member returns to substantially atmospheric pressure and that member refills with liquid from the reservoir pot it ready for a repeat cycle.

The valving action for the withdrawal pipe 26 of the particular embodiment illustrated is achieved by providing a segment of the withdrawal pipe above the normal liquid level. This is an especially suitable design for a pump handling molten metal. Other valving means may be employed such as a spring loaded valve for a pump used to transfer low density liquids. A pump de signed for use with corrosive liquid may be lined with glass.

Although an exemplary embodiment of the invention has been disclosed herein for purposes of illustration, it will be understood that various changes, modifications and substitutions may be incorporated in such embodiment without departing from the spirit of the invention as defined by the claims which follow.

I claim:

1. A liquid pump comprising:

a reservoir;

a standpipe having an open upper end disposed within the reservoir with the open upper end being located below the normal liquid level of said reservoir;

a standpipe enclosure means open at its lower end and placed about said standpipe with said opening located below the upper end of the standpipe, said opening providing liquid communication between the interior of the enclosure means and the reservoir;

means for introducing a pressurized fluid to the interior of the standpipe enclosure means above the normal liquid level therein; and

a liquid withdrawal means connecting to the standpipe for removing liquid therefrom in response to introduction of pressurized fluid to the interior of said standpipe enclosure means.

2. A liquid pump comprising:

a reservoir;

a standpipe disposed within the reservoir and having an open upper end located below the normal liquid 7 level of said reservoir;

a tubular member having an open lower end and a closed upper end placed about the standpipe with the inner wall of the tubular member spaced therefrom and with the open lower end of said tubular enclosure being spaced from the reservoir bottom and below the normal liquid level of said reservoir;

means for introducing a pressurized fluid to the interior of said tubular member above the normal liquid level therein; and

a liquid withdrawal means including a pipe connected to the standpipe below its upper end and a valving means permitting flow of liquid with the introduction of pressurized fluid to the interior of said tubular member.

3. A liquid pump in accordance with claim 2 wherein means are provided for periodically interrupting the flow of the pressurized fluid to the tubular member.

4. A liquid pump comprising:

a reservoir of relatively large cross section;

a standpipe having a cross section of significantly less area than the reservoir and having an open upper end disposed within said reservoir with the open upper end being located below the normal liquid level of said reservoir;

a tubular member having a cross section somewhat larger than the cross section of the standpipe disposed about the standpipe with its inner Wall closely spaced to said standpipe, said tubular member being closed at its 'upper end and open at its lower end with its open lower end being spaced above the bottom of the reservoir, thus providing liquid communication between the interior of the tubular member and said reservoir;

means for introducing a pressurized fluid to the interior of the tubular member above the normal liquid level therein; and

a liquid withdrawal pipe connecting to the standpipe adjacent its lower end, said withdrawal pipe having a segment above the normal liquid level of the reservoir.

5. A liquid pump in accordance with claim 4 wherein means are provided for automatically and periodically interrupting the flow of pressurized fluid to the interior of the tubular member.

6. A pump for molten metals comprising:

a reservoir having heating means for retaining the metal in its molten state;

a standpipe having an open upper end disposed within the reservoir with the open upper end of said standpipe being located below the normal molten metal level of the reservoir;

a tubular standpipe enclosure means having an open lower end disposed about said standpipe with the open end of the tubular enclosure means being disposed below the molten liquid level and with the inner wall of said tubular means being closely spaced to the standpipe;

means for introducing a pressurized fluid to the interior of the tubular standpipe enclosure means above the normal molten liquid level therein; and

a liquid withdrawal pipe connected to the standpipe adjacent its lower end, said withdrawal pipe having a segment above the normal molten metal level of the reservoir.

7. A pump in accordance with claim 6 wherein means are provided for automatically and periodically interrupting the flow of pressurized fluid to the interior of the standpipe.

8. A liquid pump comprising:

a reservoir;

:1 standpipe disposed within the reservoir and having an open upper end located below the normal liquid level of said reservoir;

a tubular member having an open lower end and a closed upper end placed about the standpipe with the inner wall of the tubular member spaced therefrom and with the open lower end of said tubular enclosure being spaced from the reservoir bottom and below the normal liquid level of said reservoir;

means for introducing a pressurized fluid to the interior of said tubular member above the normal liquid level therein; and

a liquid withdrawal pipe connecting to the standpipe adjacent its lower end, said withdrawal pipe having a segment above the normal liquid level of the reservorr.

No references cited. 

1. A LIQUID PUMP COMPRISING: A RESERVOIR; A STANDPIPE HAVING AN OPEN UPPER END DISPOSED WITHIN THE RESERVOIR WITH THE OPEN UPPER END BEING LOCATED BELOW THE NORMAL LIQUID LEVEL OF SAID RESERVOIR; A STANDPIPE ENCLOSURE MEANS OPEN AT ITS LOWER END AND PLACED ABOUT SAID STANDPIPE WITH SAID OPENING LOCATED BELOW THE UPPER END OF THE STANDPIPE, SAID OPENING PROVIDING LIQUID COMMUNICATION BETWEEN THE INTERIOR OF THE ENCLOSURE MEANS AND THE RESERVOIR; MEANS FOR INTRODUCING A PRESSURIZED FLUID TO THE INTERIOR OF THE STANDPIPE ENCLOSURE MEANS ABOVE THE NORMAL LIQUID LEVEL THEREIN; AND A LIQUID WITHDRAWAL MEANS CONNECTING TO THE STANDPIPE FOR REMOVING LIQUID THEREFROM IN RESPONSE TO INTRODUCTION OF PRESSURIZED FLUID TO THE INTERIOR OF SAID STANDPIPE ENCLOSURE MEANS. 